const log = console.log;

function longTask(){
    for(let i=0;i<1000;i++){
        let num = 0
        for(let j=0;j<1000;j++){
            num = i+j
        }
    }
}
console.time('all')
console.time('TEST');
longTask()
console.timeEnd('TEST');//判断被包裹程序执行时长，判断问题
console.time('TEST1');
longTask();
console.timeEnd('TEST1')
console.timeEnd('all');//总时长